1. Field of the Invention
The present invention relates to a method and mobile communication system capable of establishing peer-to-peer (P2P) transmission, and more particularly, to a method and mobile communication system capable of implementing P2P transmission to enhance data transmission rate and transmission throughput.
2. Description of the Prior Art
In a general packet radio service (GPRS) and a universal mobile telecommunication system (UMTS), each network application (e.g. VoIP, WAP, etc.) corresponds to an individual access point name (APN). Prior to starting a network application, a mobile station (MS), i.e. a user equipment, must activate a packet data protocol (PDP) context activation procedure between a serving GPRS support node (SGSN) and a service providing gateway GPRS support node (GGSN). A PDP context contains routing information for a packet in GPRS/UMTS network. When a PDP context activation procedure is triggered, the SGSN chooses a suitable APN to serve the user according to a service activated by the mobile station, and then seeks a suitable GGSN to serve the user. The SGSN can query a domain name server (DNS) according to the corresponding APN, to provide a set of suitable GGSN addresses. The SGSN then chooses a GGSN to start establishing the PDP context. In other words, triggering the PDP context activation procedure also means allocating an Internet protocol (IP) address to the mobile station.
Generally, there is a finite amount of IP addresses, especially for mobile communication systems, since users often far exceed allocable addresses. Therefore, mobile communication system suppliers employ dynamic host configuration protocol (DHCP) techniques, to dynamically allocate IP addresses. In other words, a system allocates an IP address to a mobile station requiring a network service, and recycles the IP address when the mobile station is turned off or when the network service is terminated. If the mobile station subsequently requires another network service, the system reallocates another IP address. As such, IP addresses may be reused to reduce wastage of network resources.
As can be seen from the above, whenever the mobile station is turned off or the network service is terminated, allocated IP addresses are recycled, and mobile stations do not have fixed IP addresses. As such, it is difficult for a mobile station to establish a P2P transmission, or other similar data connections with another mobile station. Therefore, it is necessary to improve over the prior art.